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1.
S Aiumlamai H Kindahl G Fredriksson L E Edqvist L Kulander O Eriksson 《Acta veterinaria Scandinavica》1992,33(2):117-127
Experimentally induced ruminal acidosis was carried out in 4 calves to investigate the possibility of resorption of endotoxins from Gram negative bacteria originating from the gastro-intestinal tract. The ruminal acidosis was induced by overfeeding of oats and the effect was evaluated by clinical and blood biochemical changes. Blood samples were collected every 2 h for 60 h before and after experimental feeding. The animals showed signs of ruminal acidosis and also the clinical and blood biochemical changes were similar to those seen after experimental endotoxaemia. However, although being less dramatic the changes in many relevant parameters such as an increase in prostaglandin F metabolite levels, body temperature, endotoxins and a decrease in iron indicate that an endotoxaemic state had occurred. The results of the present study show that ruminal acidosis/stasis is linked to resorption of endotoxins from the gastro-intestinal tract causing endotoxaemia/endotoxicosis. 相似文献
2.
There was produced with Ery. rhusiopathiae a rheumatoid-like arthritis in swine, which passed successively through acute, sub-acute and chronic stages. This was typically a non-suppurative proliferative change with concurrent changes in the joint fluid.
The arthritis was shown to persist even though the initial inciting agent could not be isolated from the advanced cases of chronic polyarthritis. This strongly suggests that the pathological process responsible for this arthritis can become autonomic and probably is related to a state of hypersensitivity.
The cellular changes observed in the synovial fluid did not differ markedly from those of rheumatoid arthritis in man. Synovial fluid mucinous changes were apparent in the decreased viscosity observed grossly. Definite changes in the character of the precipitate produced by acetic acid treatment of the fluid were also observed.
相似文献3.
This study was designed to clarify the characteristics of changes in plasma concentrations of reproductive hormones in heifers from birth to puberty. Weekly or daily hormonal changes were observed in 39 heifers. Daily changes in the concentration of follicle-stimulating hormone (FSH) demonstrated a consistent cycle of hormone changes over a 7- to 8-day period in heifers from approximately 10 days to 9 months old. Weekly changes in reproductive hormones showed that there were three brief periods in heifers between birth and puberty in which dramatic changes occur. The first period was the first week after birth, during which a reciprocal relationship between steroid hormones and gonadotropins was observed. At birth, the concentrations of steroid hormones were higher than those at any other age. These hormone levels rapidly decreased within the first week after birth. Gonadotropin levels, however, increased from birth to 1 week of age. The second period of major change was at approximately 4 weeks of age when there was an increase in the concentrations of luteinizing hormone (LH), estradiol-17beta, testosterone, and immunoreactive inhibin. The third period was the last 5 weeks before the first ovulation, when there was an increase in the concentrations of estradiol-17beta followed by an increase in (LH). These results suggest that regular hormone changes start from 10 days after birth and that the periods from birth to 4 weeks of age and the last 5 weeks before the first ovulation in heifers are important to the development of reproductive functions before puberty. 相似文献
4.
Two hundred and fifty-two teats from the udder quarters of 68 dairy cows were studied by bacteriological examination of quarter milk samples and microscopic examination of the teats. Of 252 quarters, 169 teats showed inflammatory changes, while 83 were of normal appearance. The inflammatory changes consisted of either neutrophil infiltrations, mononuclear cell infiltrations and fibrosis, or a combination of these changes. The reaction was restricted to the teat cisterns and/or Fürstenberg's rosettes, but very rarely also in the teat canal. In 136 of 169 cases, the inflammatory reaction was associated with bacteria in the milk, while in 33 cases no bacteria could be recovered from milk, in spite of inflammatory changes in the teat structures. Only 36 of 83 of normal teats were bacteriologically positive. 相似文献
5.
Sterile intrauterine autolysis was experimentally produced in 28 ovine fetuses in the last 3rd of gestation by umbilical artery ligation. The fetuses were retrieved by cesarean section after periods of sterile intrauterine autolysis ranging from 0.5 to 168 hours. The following autolytic changes, frequently reported as significant lesions in infectious abortions in cattle and sheep, were observed: subcutaneous blood-tinged gelatinous edema, blood-tinged fluid in the serous cavities, renal cortical softening, uniform reddish brown tissues, hepatic friability and mottling, and cloudy yellow to cloudy red abomasal contents. The appearance of these and other autolytic changes corresponded to sterile sequential autolytic changes reported in the rabbit fetus and used to determine duration of retention of stillborn infants and are of comparative biomedical significance. The sequential autolytic changes may be used as an index to duration of retention after death of a ruminant fetus and provide a basis for reappraising various infective abortifacients common to ruminants by allowing separation of specific lesions from strictly autolytic changes. 相似文献
6.
The signs shown by 96 dogs recovering at home after day-case soft tissue operations were assessed by their owners for three days. On the day of the operation there were behavioural changes in all the animals, but by two days after the operation changes in behaviour were detected in only 85 per cent of them. The most common changes were in the dogs' demeanour and their way of moving; there were decreases in overall activity and playfulness, and increases in contact seeking. The dogs also showed signs of pain: the highest ratings were observed on the day of the operation, when the median value on a visual analogue scale from 0 to 100 mm was 43 mm, with a range from 0 to 95 mm. The type of operation significantly affected the signs observed. 相似文献
7.
Nephrotoxicity of sodium arsenate in dogs 总被引：1，自引：0，他引：1
H Tsukamoto H R Parker D H Gribble A Mariassy S A Peoples 《American journal of veterinary research》1983,44(12):2324-2330
Nephrotoxicity of sodium arsenate was evaluated in dogs to determine the pathophysiologic basis for renal lesions caused by this heavy metal. Examination of biopsy specimens indicated that the low dose of the As salt (0.73 mg/kg of body weight) produced histologic changes consisting of mild degeneration and vacuolation of renal tubular epithelium. Vacuolation involved mainly the ascending thick portion of the nephron. Clinical pathologic changes were not demonstrable at this dosage level according to glomerular filtration rate (creatinine clearance), fractional reabsorption of sodium, potassium, and chloride; plasma osmolar and free water clearance; and urinalysis. The medium dose (7.33 mg/kg) resulted in alterations determined by urinalysis, but did not markedly affect other clinical pathologic measurements. Histopathologic changes were equal to or greater than those seen with the low dose. Tubular necrosis was observed in the cortical portion of the nephron and the ascending thick limb. The high dose (14.66 mg/kg) consistently produced marked changes in all parameters evaluated. Clinical pathologic alterations were compatible with acute tubular necrosis involving all segments of the nephron. Histologically, moderate glomerular sclerosis and severe tubular necrosis were observed. During recovery from the high dose of As, a gradual compensatory healing process was observed that was evident in all clinical pathologic parameters and was confirmed from sequential renal biopsy specimens. 相似文献
8.
J. P. Orr G. C. McKenzie 《The Canadian veterinary journal. La revue veterinaire canadienne》1981,22(5):121-125
A very high incidence of posterior paresis in growing calves was casued by abnormal development of the vertebral column. The pathological changes were focal premature synostoses of vertebral growth plates with resulting reduction in size of the vertebral canal. Malacic changes were seen in sections from all areas of the spinal cord. Abnormalities in growth of the cranium and appendicular skeleton were also present. The growth plates in the cranial base were prematurely closed and the cranial cavity was shortened. Long bones were shortened and distorted. Possible causes include teratogenic plants or chemicals, mineral deficiencies, and hypervitaminosis A. 相似文献
9.
Sunflower cake (SC), horse bean (HB), and alfalfa meal (AM) were treated with rising doses of formaldehyde (F) from 0.0, 0.2 ... 2.0 g F per 100 g crude protein. We have followed the differences of crude protein solubility, its degradability and disappearance of dry matter in the rumen as well as the amount of reversible bonded F from the F dose. With AM it was found a significant influence of ADF on the degradability and on the amount of acid-labile bonded F and/or on the decrease of N solubility. From the total N content the share of soluble nitrogen decreased in SC by 31%, HB by 24%, and in AM only by 12.5%. With the increase of the F dose its protective effect on proteins against the degradability mainly in SC and HB also rose significantly. The degradability of AM protein was influenced more by the incubation time than by the effect of treatment. The degradability of the SC proteins fell from 95% with untreated to 27% treated with the maximum dose. With AM it fell slowly from 84% to 74% by the determination coefficient R2 = 0.77. It was observed a marked decrease in HB only from the dose of 1.28% F. The changes in dry matter disappearance were similar to the changes in crude protein degradability and to the changes of solubility in SC and AM. The in situ method proved very suitable for the determination of the extent of degradability of the feed proteins in the rumen. 相似文献
10.
Ultrastructural postmortem changes of glomeruli, proximal tubules (PT), distal tubules (DT), and cortical collecting ducts (CD) were studied in adult chickens held at 27 C for 0, 1, 5, 10, 30, 60, or 360 minutes. There were marked ultrastructural alterations in tissues considered normal by light microscopy. The earliest changes, evident in immediately fixed samples, consisted of apical cell swelling of PT and DT epithelium and formation of smaller projections from glomerular capillary endothelium. Swelling increased with time, and gaps in cell membranes of tubular cytoplasmic blebs were evident by 10 minutes postmortem. The urinary space also contained cellular debris in immediately fixed samples and was filled by swollen epithelial cells by 10 minutes postmortem. Organelle changes were pronounced by 5 minutes in PT epithelium and by 10 minutes in DT epithelium. These initial changes consisted of dilation of mitochondrial and endoplasmic reticulum. Flocculent mitochondrial matrix densities were present by 5 minutes in PT epithelium and enlarged and appeared in other tubular segments as the time postmortem increased. Nuclear chromatin margination occurred first in 10-minute samples of PT and DT, and it was present by 30 minutes in glomerular epithelial cells. Chromatin clumping was present in PT and DT epithelium at 30 minutes and was followed by pyknosis and karyorrhexis at 360 minutes. These latter nuclear changes were not found in glomerular cells during the study. Nuclei of CD showed little change during the periods studied. The glomerular basement membrane appeared as a single hyaline membrane by 30 minutes postmortem, but this membrane and podocyte foot processes showed little further change by 360 minutes postmortem. 相似文献
11.
The changes in ammonia content and pH values in beef and pork stored at different temperatures were studied in relation with sensory changes. Samples were taken from the stored meat at a temperature of +3 degrees C in the 0th, 12th, 36th, 60th, 84th, 108th and 132nd hour and at a temperature of +10 degrees C in the 0th, 6th, 24th, 36th, 54th, 72nd and 84th hour. The quantity of ammonia in the samples was determined by means of an ion-selective electrode. The pH value was determined potentiometrically. The kinds of meat (pork, beef) differed in the development of ammonia content. Ammonia content was found to be directly dependent on storage temperature. A similar relation was observed in the development of pH values. The sensory changes of stored meat were parallel to the changes in ammonia levels and pH values. The results can be used for an evaluation of the degree of biochemical changes in the meat and of the fitness of the raw material to the production of tins for long storage. Advantageous points are seen in the rapid and objective determination of ammonia content by the ion-selective electrode and the determination of the pH value by means of the combined glass electrode with the aid of the same apparatus. 相似文献
12.
C. A. Jones K. R. Refsal A. C. Lippert R. F. Nachreiner M. M. Schwacha 《Domestic animal endocrinology》1990,7(4):559-572
In Experiment 1, voided urine samples were collected from 12 adult dogs at 0500, 1400, and 2200 hr for 4 days. Cortisol was measured in unextracted urine by radioimmunoassay, creatinine by spectrophotometry, and the cortisol/creatinine ratio (UCCR) was calculated for each sample. There was considerable variation both within and among dogs in UCCR but there was no consistent time of day fluctuation in UCCR. In Experiment 2, these dogs were randomly assigned to 1 of 4 groups. The groups received each of 4 treatments (saline, dexamethasone, ACTH gel, and aqueous ACTH) at 7 day intervals in a Latin square design. All urine was collected from 0 through 8 hr. Blood samples were collected at 20 minute intervals from 0 through 8 hr. Plasma cortisol exposure was determined by quantifying area under the curve (AUC). UCCR measurement was shown to differentiate basal from elevated, but not lowered, cortisol secretion. A positive linear relationship between UCCR and AUC was seen for all treatments except dexamethasone. These results indicate that changes in cortisol secretion are reflected in changes in UCCR, but measurement of UCCR may lack sensitivity to differentiate basal from reduced states of cortisol secretion. In Experiment 3, urine was collected daily before and during induction therapy with o,p′-DDD from dogs with pituitary-dependent hyperadrenocorticism. Successful suppression of the adrenal glands was accompanied by a progressive decrease in UCCR. There was considerable variation in the rate of adrenal suppression. 相似文献
13.
Comparative pharmacokinetics of gentamicin, neomycin and oxytetracycline in newborn calves 总被引：1，自引：0，他引：1
G. E. BURROWS P. B. BARTO† B. MARTIN 《Journal of veterinary pharmacology and therapeutics》1987,10(1):54-63
The pharmacokinetics of three antibiotics--gentamicin, neomycin and oxytetracycline were determined in newborn calves. The kinetic determinations, using two-compartment open models, were made at increasing ages from 1 day to 42 days and compared with those made from older calves (250+ days). Although all three antibiotics are eliminated unchanged primarily by glomerular filtration, there were marked differences in the development of elimination processes for individual drugs. The pharmacokinetics of neomycin were not influenced by age. Although the elimination half-life of gentamicin appeared to decrease with age, the changes were not significant and were due to an increased elimination rate in only one calf. There was no change with age in the remaining three calves. Oxytetracycline elimination was significantly reduced in newborn calves. This was exemplified by a decrease in the half-life of elimination t1/2 (beta) from 672.5 +/- 99.4 in the newborn to 385.6 +/- 76.8 at 6 weeks of age, and 377.3 +/- 40.8 min in the 250-day-old calf. These changes were consistent in all four calves. The rate of elimination remained low for the first 4 weeks of life. The volume of distribution Vd, area was not changed after the first week of life. Based on pharmacokinetic changes, an adjustment of dosage is indicated for oxytetracycline in the newborn calf as compared to the older calf or adult. 相似文献
14.
Grassland is a major vegetation type in Xinjiang Province,and is an important component of carbon source-sink calculations. It is therefore important to ecological management decisions to understand the factors driving changes in grassland quality and likely future trends in those changes. We used geographic information maps to eliminate the interference of human activities and determine changes in grassland status and areas of stable grassland from 1980 to 2020,and analyzed changes in grassland quality and its response to climate change using data such as normalized vegetation index（NDVI）,vegetation net primary productivity（NPP）,and meteorological data,among others. We here estimate changes in grassland quality in Xinjiang and predict grassland quality changes from 2021 to 2040 using the Thornthwaite Memorial model and other models. We found that：1） The grassland quality in Xinjiang was generally increasing,with a statistically significant rate of ongoing increase. The grassland cover and quality in mountainous areas of Xinjiang was high,while that at the desert edge was low. 2）The main driving forces for grassland quality changes in Xinjiang are temperature and precipitation. The correlation between grassland quality and precipitation was positive. Temperatures exceeding a certain limit were found to inhibit grassland quality. Sensitivity to temperature and precipitation decline was found to be greater when vegetation cover was lower. 3）The grassland quality and its temporal and spatial changes in Xinjiang can be reflected by climatic productivity. The lower the grassland cover,the stronger was the link between grassland quality and climate factors. 4）Under currently predicted climate change scenarios,the quality of low-cover grassland will be improved in the future,while the quality of other categories will tend to decrease. This information on grassland quality in Xinjiang and its predicted future trends can assist in formulating ecological protection measures and in other ways,such as compilation of carbon stock inventories. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved. 相似文献
15.
Early immune responses in experimental maedi 总被引：2，自引：0，他引：2
L Sihvonen 《Research in veterinary science》1981,30(2):217-222
Ten Finnish sheep were infected with maedi virus either by the respiratory tract or by intracerebral injection. After respiratory tract infection, virus specific lymphocyte stimulation was detected between two and seven weeks and complement fixing antibodies between seven weeks and three months. After intracerebral injection, lymphocyte stimulation was detected between five and nine weeks and complement fixing antibodies between nine weeks and four months. Neutralising antibodies were not found in six sheep killed within four months but were found in two of four sheep four and five months after infection. Virus was recovered with varying frequency from the peripheral blood leucocytes and tissues of all the sheep and also from the cerebrospinal fluid of intracerebrally inoculated sheep. The histological changes in sheep inoculated via the respiratory tract were comparable to known early maedi lesions; no changes were found in the central nervous system (CNS). The intracerebrallly inoculated sheep showed very mild periventricular inflammation in the CNS. 相似文献
16.
T S Kellerman G L Erasmus J A Coetzer J M Brown B P Maartens 《The Onderstepoort journal of veterinary research》1991,58(1):47-53
Geeldikkop was induced in sheep by the oral administration of crude steroidal saponins from Tribulus terrestris. Two of the sheep developed typical lesions of geeldikkop, including birefringent crystalloid material in bile ducts and concentric periductal lamellar fibrosis. The clinical pathological changes in these sheep were also consistent with those of geeldikkop: aspartate transaminase and gamma-glutamyl transferase activities in the sera of both were elevated, and one had bilirubinaemia. A third sheep became photosensitive without typical lesions of geeldikkop in the liver or changes in the activities of liver enzymes before euthanasia. The findings of these trials are consistent with reports from abroad that ovine hepatogenous photosensitization, caused by Agave lechuguilla and Narthecium ossifragum, can be induced with crude saponins from the respective plants. 相似文献
17.
Van Heel MC Moleman M Barneveld A Van Weeren PR Back W 《Equine veterinary journal》2005,37(6):536-540
REASONS FOR PERFORNING STUDY: In order to optimise shoeing and shoeing conditions, it is essential to know how the horse adapts to a common shoeing interval. OBJECTIVES: To measure changes in location of the centre of pressure (CoP) and hoof-unrollment pattern during a shoeing interval and to assess whether these changes in CoP result directly from changes in hoof conformation or are also influenced by compensatory mechanisms. METHODS: Eighteen horses were trotted over a pressure-force measurement system shortly after shoeing and 8 weeks later. The position of the CoP was measured and also predicted using calculations based on changes in hoof conformation. RESULTS: The measured shift in CoP was less than calculated. This difference was largest in the hind feet. The hoof-unrollment pattern stayed basically the same in the front feet, but in the hind feet there was a substantial lateral shift of the trajectory of the CoP. CONCLUSIONS: Horses can compensate, to a certain extent, for changes in hoof conformation that develop during 8 weeks on shoes. As the capacity to compensate is less in the forelimbs, the relative increase in loading of these limbs during a shoeing interval is larger than in the hindlimbs. Potential relevance: This study provides essential basic data for the development of science-based shoeing techniques. 相似文献
18.
Viability and Ultrastructural Changes in Group E Streptococci After in vitro Phagocytosis by Swine Macrophages 
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下载免费PDF全文 The loss of viability and ultrastructural changes were studied in group E Streptococci (GES) after in vitro phagocytosis in immune swine macrophages. There was a 50% reduction in the viability of intracellular GES during the first 60 minutes of incubation and a total loss of viability by 300 minutes as compared to the control tubes where the GES increased.
Loss of viability in phagocytized group E Streptococci was associated with the appearance of degenerative changes in the bacterial cytoplasm. This was followed by disruption of the bacterial cell membrane and its separation from the bacterial cell wall. No definite evidence of cell wall degeneration could be found. Unphagocytized organisms incubated for similar periods and fixed in the same manner did not lose viability nor have any degenerative changes.
相似文献19.
内蒙古阿里河地区近年冻土变化特征分析 《畜牧与饲料科学》2016,37(8):90-90
利用1981—2010年内蒙古鄂伦春自治旗气象局常规观测资料,分析了内蒙古鄂伦春自治旗阿里河地区冻土深度的变化及其与气候变化的关系。结果表明,近30年期间阿里河地区的冻土深度呈逐渐增加趋势,趋势率为7.23 cm/10年;终止日期提前趋势程度大于起始日期提前程度,表明冻土期将变短。冻土深度的变化与雪深、气温和降水的变化均呈负相关。 相似文献
20.
O Ladefoged 《Acta veterinaria Scandinavica》1978,19(4):479-486
The action of bacterial endotoxin on the pharmacokinetics of warfarin was investigated in rabbits injected with bacterial endotoxin from E. coli. High doses of endotoxin were able to change the kinetics of warfarin in rabbits by changing its volume of distribution. It is not possible to conclude whether the changes in elimination rate of warfarin in rabbits were mediated through changes in liver blood flow or through impairment of the metabolic capacity of the liver cells. 相似文献